A growing number of people, millions worldwide, say they believe that life definitively ends at death – that there is no God, no afterlife and no divine plan. And it’s an outlook that could be gaining momentum – despite its lack of cheer. In some countries, openly acknowledged atheism has never been more popular.

“There’s absolutely more atheists around today than ever before, both in sheer numbers and as a percentage of humanity,” says Phil Zuckerman, a professor of sociology and secular studies at Pitzer College in Claremont, California, and author of Living the Secular Life. According to a Gallup International survey of more than 50,000 people in 57 countries, the number of individuals claiming to be religious fell from 77% to 68% between 2005 and 2011, while those who self-identified as atheist rose by 3% – bringing the world’s estimated proportion of adamant non-believers to 13%.

While atheists certainly are not the majority, could it be that these figures are a harbinger of things to come? Assuming global trends continue might religion someday disappear entirely?

It’s impossible to predict the future, but examining what we know about religion – including why it evolved in the first place, and why some people chose to believe in it and others abandon it – can hint at how our relationship with the divine might play out in decades or centuries to come.

Scholars are still trying to tease out the complex factors that drive an individual or a nation toward atheism, but there are a few commonalities. Part of religion’s appeal is that it offers security in an uncertain world. So not surprisingly, nations that report the highest rates of atheism tend to be those that provide their citizens with relatively high economic, political and existential stability. “Security in society seems to diminish religious belief,” Zuckerman says. Capitalism, access to technology and education also seems to correlate with a corrosion of religiosity in some populations, he adds.

Crisis of faith

Japan, the UK, Canada, South Korea, the Netherlands, the Czech Republic, Estonia, Germany, France and Uruguay (where the majority of citizens have European roots) are all places where religion was important just a century or so ago, but that now report some of the lowest belief rates in the world. These countries feature strong educational and social security systems, low inequality and are all relatively wealthy. “Basically, people are less scared about what might befall them,” says Quentin Atkinson, a psychologist at the University of Auckland, New Zealand.

Yet decline in belief seems to be occurring across the board, including in places that are still strongly religious, such as Brazil, Jamaica and Ireland. “Very few societies are more religious today than they were 40 or 50 years ago,” Zuckerman says. “The only exception might be Iran, but that’s tricky because secular people might be hiding their beliefs.”

The US, too, is an outlier in that it is one of the wealthiest countries in the world, but also has high rates of religiosity. (Still, a recent Pew survey revealed that, between 2007 and 2012, the proportion of Americans who said they are atheist rose from 1.6% to 2.4%.)

Decline, however, does not mean disappearance, says Ara Norenzayan, a social psychologist at the University of British Columbia in Vancouver, Canada, and author of Big Gods. Existential security is more fallible than it seems. In a moment, everything can change: a drunk driver can kill a loved one; a tornado can destroy a town; a doctor can issue a terminal diagnosis. As climate change wreaks havoc on the world in coming years and natural resources potentially grow scarce, then suffering and hardship could fuel religiosity. “People want to escape suffering, but if they can’t get out of it, they want to find meaning,” Norenzayan says. “For some reason, religion seems to give meaning to suffering – much more so than any secular ideal or belief that we know of.”

This phenomenon constantly plays out in hospital rooms and disaster zones around the world. In 2011, for example, a massive earthquake struck Christchurch, New Zealand – a highly secular society. There was a sudden spike of religiosity in the people who experienced that event, but the rest of the country remained as secular as ever. While exceptions to this rule do exist – religion in Japan plummeted following World War II, for instance – for the most part, Zuckerman says, we adhere by the Christchurch model. “If experiencing something terrible caused all people to become atheists, then we’d all be atheists,” he says.

The mind of god

But even if the world’s troubles were miraculously solved and we all led peaceful lives in equity, religion would probably still be around. This is because a god-shaped hole seems to exist in our species’ neuropsychology, thanks to a quirk of our evolution.

Understanding this requires a delve into “dual process theory”. This psychological staple states that we have two very basic forms of thought: System 1 and System 2. System 2 evolved relatively recently. It’s the voice in our head – the narrator who never seems to shut up – that enables us to plan and think logically.

System 1, on the other hand, is intuitive, instinctual and automatic. These capabilities regularly develop in humans, regardless of where they are born. They are survival mechanisms. System 1 bestows us with an innate revulsion of rotting meat, allows us to speak our native language without thinking about it and gives babies the ability to recognise parents and distinguish between living and nonliving objects. It makes us prone to looking for patterns to better understand our world, and to seek meaning for seemingly random events like natural disasters or the death of loved ones.

In addition to helping us navigate the dangers of the world and find a mate, some scholars think that System 1 also enabled religions to evolve and perpetuate. System 1, for example, makes us instinctually primed to see life forces – a phenomenon called hypersensitive agency detection – everywhere we go, regardless of whether they’re there or not. Millennia ago, that tendency probably helped us avoid concealed danger, such as lions crouched in the grass or venomous snakes concealed in the bush. But it also made us vulnerable to inferring the existence of invisible agents – whether they took the form of a benevolent god watching over us, an unappeased ancestor punishing us with a drought or a monster lurking in the shadows.

Similarly, System 1 encourages us to see things dualistically, meaning we have trouble thinking of the mind and body as a single unit. This tendency emerges quite early: young children, regardless of their cultural background, are inclined to believe that they have an immortal soul – that their essence or personhood existed somewhere prior to their birth, and will always continue to exist. This disposition easily assimilates into many existing religions, or – with a bit of creativity – lends itself to devising original constructs.

“A Scandinavian psychologist colleague of mine who is an atheist told me that his three-year-old daughter recently walked up to him and said, ‘God is everywhere all of the time.’ He and his wife couldn’t figure out where she’d gotten that idea from,” says Justin Barrett, director of the Thrive Center for Human Development at Fuller Theological Seminary in Pasadena, California, and author of Born Believers. “For his daughter, god was an elderly woman, so you know she didn’t get it from the Lutheran church.”

For all of these reasons, many scholars believe that religion arose as “a byproduct of our cognitive disposition”, says Robert McCauley, director of the Center for Mind, Brain and Culture at Emory University in Atlanta, Georgia, and author of Why Religion Is Natural and Science Is Not. “Religions are cultural arrangements that evolved to engage and exploit these natural capacities in humans.”

Hard habits to break

Atheists must fight against all of that cultural and evolutionary baggage. Human beings naturally want to believe that they are a part of something bigger, that life isn’t completely futile. Our minds crave purpose and explanation. “With education, exposure to science and critical thinking, people might stop trusting their intuitions,” Norenzayan says. “But the intuitions are there.”

On the other hand, science – the system of choice that many atheists and non-believers look to for understanding the natural world – is not an easy cognitive pill to swallow. Science is about correcting System 1 biases, McCauley says. We must accept that the Earth spins, even though we never experience that sensation for ourselves. We must embrace the idea that evolution is utterly indifferent and that there is no ultimate design or purpose to the Universe, even though our intuition tells us differently. We also find it difficult to admit that we are wrong, to resist our own biases and to accept that truth as we understand it is ever changing as new empirical data are gathered and tested – all staples of science. “Science is cognitively unnatural – it’s difficult,” McCauley says. “Religion, on the other hand, is mostly something we don’t even have to learn because we already know it.”

“There’s evidence that religious thought is the path of least resistance,” Barrett adds. “You’d have to fundamentally change something about our humanity to get rid of religion.” This biological sticking point probably explains the fact that, although 20% of Americans are not affiliated with a church, 68% of them say that they still believe in God and 37% describe themselves as spiritual. Even without organised religion, they believe that some greater being or life force guides the world.

Similarly, many around the world who explicitly say they don’t believe in a god still harbour superstitious tendencies, like belief in ghosts, astrology, karma, telepathy or reincarnation. “In Scandinavia, most people say they don’t believe in God, but paranormal and superstitious beliefs tend to be higher than you’d think,” Norenzayan says. Additionally, non-believers often lean on what could be interpreted as religious proxies – sports teams, yoga, professional institutions, Mother Nature and more – to guide their values in life. As a testament to this, witchcraft is gaining popularity in the US, and paganism seems to be the fastest growing religion in the UK.

Religious experiences for non-believers can also manifest in other, more bizarre ways. Anthropologist Ryan Hornbeck, also at the Thrive Center for Human Development, found evidence that the World of Warcraft is assuming spiritual importance for some players in China, for example. “WoW seems to be offering opportunities to develop certain moral traits that regular life in contemporary society doesn’t afford,” Barrett says. “People seem to have this conceptual space for religious thought, which – if it’s not filled by religion – bubbles up in surprising ways.”

The in-group

What’s more, religion promotes group cohesion and cooperation. The threat of an all-powerful God (or gods) watching for anyone who steps out of line likely helped to keep order in ancient societies. “This is the supernatural punishment hypothesis,” Atkinson says. “If everyone believes that the punishment is real, then that can be functional to groups.”

And again, insecurity and suffering in a population may play a role here, by helping to encourage religions with stricter moral codes. In a recent analysis of religious belief systems of nearly 600 traditional societies from around the world, Joseph Bulbulia at the University of Wellington, New Zealand and his colleagues found that those places with harsher weather or that are more prone to natural disasters were more likely to develop moralising gods. Why? Helpful neighbours could mean the difference between life and death. In this context, religion evolved as a valuable public utility.

“When we see something so pervasive, something that emerges so quickly developmentally and remains persistent across cultures, then it makes sense that the leading explanation is that it served a cooperative function,” says Bulbulia.

Finally, there’s also some simple mathematics behind religion’s knack for prevailing. Across cultures, people who are more religious also tend to have more children than people who are not. “There’s very strong evidence for this,” Norenzayan says. “Even among religious people, the more fundamentalist ones usually have higher fertility rates than the more liberal ones.” Add to that the fact that children typically follow their parents’ lead when it comes to whether or not they become religious adults themselves, and a completely secularised world seems ever more unlikely.

Enduring belief

For all of these reasons – psychological, neurological, historical, cultural and logistical – experts guess that religion will probably never go away. Religion, whether it’s maintained through fear or love, is highly successful at perpetuating itself. If not, it would no longer be with us.

And even if we lose sight of the Christian, Muslim and Hindu gods and all the rest, superstitions and spiritualism will almost certainly still prevail. More formal religious systems, meanwhile, would likely only be a natural disaster or two away. “Even the best secular government can’t protect you from everything,” says McCauley. As soon as we found ourselves facing an ecological crisis, a global nuclear war or an impending comet collision, the gods would emerge.

“Humans need comfort in the face of pain and suffering, and many need to think that there’s something more after this life, that they’re loved by an invisible being,” Zuckerman says. “There will always be people who believe, and I wouldn’t be surprised if they remain the majority.”

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